(長安大學(xué) 環(huán)境科學(xué)與工程學(xué)院，西安 710054)
摘 要: 分別用固相法和液相法制備Y2Cu2O5光催化劑，利用熱重−差熱分析(TG-DTA)、X射線衍射(XRD)、掃描電子顯微鏡(SEM)、紫外−可見光漫反射光譜(UV-Vis DRS)等技術(shù)對光催化劑進(jìn)行表征。在模擬太陽光照射條件下，以草酸(H2C2O4)為犧牲劑對所制得的光催化劑制氫性能進(jìn)行評價(jià)，考察制備方法和犧牲劑類型等因素對其產(chǎn)氫性能的影響以及光催化劑的穩(wěn)定性能。結(jié)果表明：溶膠−凝膠法所得樣品中含有Y2O3雜質(zhì)，為Y2Cu2O5與Y2O3的混合物；固相法所得樣品為純凈的Y2Cu2O5，具備較高的光催化產(chǎn)氫活性。用固相法制備的光催化劑Y2Cu2O5，當(dāng)其用量為0.8 g/L、草酸為犧牲劑且初始濃度為0.05 mol/L時(shí)，表現(xiàn)出最佳光催化產(chǎn)氫活性，其產(chǎn)氫量為3.78 mmol/(h∙g)。但Y2Cu2O5在草酸溶液中不穩(wěn)定，會(huì)與草酸反應(yīng)生成Y2(C2O4)3∙2H2O，導(dǎo)致產(chǎn)氫活性降低。
關(guān)鍵字: Y2Cu2O5；光催化；產(chǎn)氫；模擬太陽光
（School of Environmental Engineering, Changan University, Xi’an 710054, China）
Abstract:Y2Cu2O5 photocatalyst was successfully synthesized via solid state reaction and sol-gel method, respectively. The thermogravimetry and differential thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet visible diffuse reflectance absorption spectra (UV-Vis DRS) were employed to characterize the as-synthesized Y2Cu2O5 products. The photocatalytic H2 evolution activity of the as-obtained samples was evaluated from oxalic acid solution used as sacrificial reagent under simulated sunlight irradiation. The influences of synthesis methods and sacrificial reagent types on the photocatalytic H2 evolution activity and durability of the as-obtained photocatalyst were investigated in detail. The results show that the sample synthesized by sol-gel method is mixture of Y2Cu2O5 and Y2O3, while that synthesized by solid state reaction is pure Y2Cu2O5 photocatalyst that exhibits better photocatalytic H2 evolution activity. When the concentration of the photocatalyst synthesized by solid state reaction is 0.8 g/L, the oxalic acid is used as the sacrificial reagent, and the initial concentration is 0.05 mol/L, the highest photocatalytic H2 evolution activity (3.78 mmol/(h∙g)) is obtained over the as-synthesized Y2Cu2O5 photocatalyst. But Y2Cu2O5 photocatalyst is also unstable in the oxalic acid solution, and can change into Y2(C2O4)3∙2H2O, which will decrease the photocatalytic H2 evolution activity.
Key words: Y2Cu2O5; photocatalysis; H2 production; simulated sunlight irradiation
